Juliet Kaarbo et al – Written Evidence (TWP0002)

Juliet Kaarbo, Professor of Foreign Policy, University of Edinburgh

Benjamin Martill, Lecturer in Politics and International Relations, University of Edinburgh

Falk Ostermann, Assistant Professor of International Relations, Justus Liebig University Giessen

Wolfgang Wagner, Professor of International Security, Vrije Universiteit Amsterdam


The International Treaty Ratification Votes Database Project


This submission builds upon evidence from the International Treaty Ratification Votes Database (ITRVD) project, an international consortium of scholars, including the authors of this study, which is sponsored by the Gerda-Henkel Foundation. The International Treaty Ratification Votes Database project has begun gathering data on the parliamentary scrutiny of international agreements in the UK, France, Germany, Canada, the Czech Republic, Finland, Ireland, Italy, the Slovak Republic, Spain, Turkey and the USA. For more information see the project homepage: www.treatyratificationvotes.eu.


Executive Summary


1.1  The UK Parliament has very limited scrutiny over the significant number of treaties signed by the UK every year, with a very limited number subject to a vote. The existing process for scrutiny suffers from collective action failure and lacks efficacy.


1.2   Parliament’s role should be revisited in light of four factors: the general trend towards empowering parliaments, the increasing domestic consequences of international treaties, the growing irrelevance of the distinction between monist and dualist legal systems, and the return of treaty competencies to the UK post-Brexit.


1.3   Comparative data from the International Treaty Ratification Votes Database project show considerable divergence across countries when it comes to the proportion of international agreements which come before legislatures, the means they use to decide where scrutiny is warranted, the form this scrutiny takes, and the level of involvement of sub-national territories and secondary chambers.


1.4  It is a given that greater politicisation would result from any increase in Parliament’s treaty competences. Existing studies suggest that voting will be influenced by a number of background political factors, including partisan affiliations, coalition politics, public opinion, prime ministerial leadership style, government-opposition dynamics and historical analogies.


1.5   The role of Parliament in treaty scrutiny needs to be understood holistically, taking into account the ‘shadow’ of the ratification vote over the negotiating process, the dynamic role of parliaments as both a constraining and enabling actor in the negotiations, the complex value trade-offs involved in empowering Parliament, and the interaction of any changes with existing aspects of the Westminster party system.


The Role of the UK Parliament in Scrutinising Treaties


2.1  Making international agreements is a key part of any state’s foreign policy. According to the World Treaty Index (Pearson, 2001, Poast et al., 2010), 75,000 treaties have been negotiated in the 20th century, most of them bilateral agreements. The UK has been amongst the countries most active in negotiating treaties (Poast et al., 2010).


2.2   However, the UK Parliament has a very limited role in scrutinising international treaties. Scrutiny is limited to the twenty-one-day sitting period for which the government must lay treaties before Parliament. Parliament does not contribute to the negotiating mandate nor does it have any formal role in the government’s conduct of the subsequent negotiations.


2.3   While both Houses of Parliament may resolve to reject a treaty before the House under existing arrangements, the procedure for doing so requires that parliamentarians obtain time for a vote and then offers only the power of delay. The process is characterised by collective action failure and lacks efficacy. It does not empower Parliament to challenge the government.


2.4   The UK Parliament’s role should be revisited in light of a number of global and domestic factors:


2.4.1.  There has been a general trend towards strengthening the role of parliament in external relations (Raunio and Wagner, 2017). This trend includes the proliferation of votes on military interventions (Kaarbo and Kenealy, 2017, Ostermann, 2017, Strong 2014, Wagner et al., 2017, Wagner, 2020), a strengthening of parliaments in the realm of arms export controls (Cops et al., 2017) and, last not least in the realm of treaty ratifications (Lantis, 2009).


2.4.2  International treaties have increasingly significant domestic effects (Conceição-Heldt 2011). The focus of trade agreements in particular has shifted from the reduction of tariffs and quotas to the reduction of non-tariff barriers and the harmonisation of domestic laws and standards. Insofar as agreements have distributional effects at the domestic level, the limitations on Parliament’s role may be seen as a democratic deficit.


2.4.3  The distinction between ‘monist’ and ‘dualist’ legal systems, in which the latter conceives of international and domestic (‘municipal’) law as distinct spheres, is increasingly considered blurred in practice and thus of limited help to account for different procedures of domestic ratification (Verdier and Versteeg, 2015). It is no-longer credible to justify British exceptionalism on the basis of this distinction.


2.4.4    Brexit will return from the EU competences to negotiate international trade treaties. Treaties of this kind have the most discernible impact domestically, since they may (dis)empower specific sectors of the UK economy. The Brexit experience and the debate over the so-called ‘meaningful vote’ also shows that Parliament’s role in ratifying international agreements has become an issue of wider public concern.


The UK in Comparative Perspective


3.1  Data from the International Treaty Ratification Votes Database project are able to show how the UK compares to other states on legislative scrutiny of international treaties. The treaty data highlight considerable diversity of national models as well as divergence in the form and extent of scrutiny. These examples show that there is considerable variation outside the UK case and suggest a number of cases from which lessons may be drawn.


3.2   An important difference in domestic scrutiny procedures concerns the question of which international agreements need to be sent to the legislature for approval. In Belgium and in the Netherlands, for example, all treaties are subject to approval by the legislature (Kadelbach 2019: 176). In the case of the Netherlands, this implied parliament’s involvement in c. 3,500 ratification procedures since 1990, although many are ‘silently adopted’ without a vote.


3.3  Other countries distinguish politically significant agreement from insignificant ones and leave the latter to the executive to ratify without any involvement of the legislature. For example, the German Basic law (Article 59) requires the consent or participation of those bodies responsible for “treaties that regulate the political relations”. Since 1990, almost 1,000 agreements had been considered politically relevant and sent to the Bundestag – and often also the Bundesrat – for approval. The Italian constitution stipulates that parliament should have a role in treaties of ‘a political nature’ or those requiring arbitration, spending, or new legislation. In France, peace treaties, commercial treaties, those relating to international organizations, committing the finances of the state, or involving the cession, exchange or addition of territory all require legislative approval.


3.4 The case of the USA illustrates that political practice can deviate significantly from the wording of the constitutional provisions. Although Article 2, Section 2 of the US constitution does not mention any exemptions to the two-thirds majority requirement in the Senate for international treaties, the 1974 Trade Act allows trade agreements to be passed by simple majorities in both houses of Congress. Moreover, so-called executive agreements that the US President may conclude unilaterally have proliferated. For the period from 1946 to 1999, more than 90% of all international agreements were executive agreements, including prominent ones like the North American Free Trade Agreement (NAFTA) (Krutz and Peake, 2009).


3.5   In some countries with federal systems, the sub-national territories (such as the Länder in Germany) participate in the ratification of some international agreements via a second chamber of parliament (such as the Bundesrat). Whether they are part of the procedure depends on the issue in question. If the issue falls under the jurisdiction of the sub-national territories, the procedure will include the Bundesrat.


The Politics of Treaty Ratification


4.1   Preliminary treaty data show that parliamentary scrutiny of international agreements has become more politicized over the last decades. In Germany, for example, the share of agreements that has been adopted unanimously has declined. These observations are in line with similar findings in other fields of foreign policy (i.e. military interventions, European affairs) (Hooghe and Marks, 2009, Wagner et al., 2018).


4.2   This suggests that parliament’s role in foreign affairs is democratically crucial against the backdrop of democratic representation and legitimate government. Indeed, politicisation should be considered a positive development insofar as it will help to connect citizens to forms of UK external engagement and allow for the mobilisation of particular interests. Politicisation may also be associated with potentially undesirable side-effects. Politicisation may make it more difficult to negotiate agreements quickly or with the necessary level of discretion. And it may risk agreements being opposed (or supported) on specific partisan or sectoral grounds rather than on the basis of the national interest broadly defined.


4.3  The effects of politicisation vary depending on the party system. In Westminster the inter- party mode of executive-legislative relations (King 1976) can result in more conflictual dynamics than in systems based on consensus or coalition government. Politicisation may be more naked in the UK, with the corresponding benefits and disbenefits.


4.4  The decision to afford Parliament a role in external affairs, and the extent of the legislature’s competences, is also the subject of political divergence (Wagner et al. 2017). Traditionally parties of the left have favoured increasing democratic control more than rightist parties, but as always different factions within these broad ideological positions have different views.


4.5  Research on parliament’s role in foreign policy suggests that the following factors can shape voting and ratification of international agreements:


4.5.1    Partisanship: Contemporary political parties tend to interpret external relations through ideological lenses. For some states, a left-right dimension is especially important (Vignoli 2019; Wagner et al., 2018). In countries like the UK which have broad-based parties there is also considerable variation between the various factions within the major parties (Kesgin and Kaarbo 2010; Kaarbo and Kenealy 2016; Martill 2018; Peake 2017).

4.5.2 Coalition Politics: Coalition cabinets’ international agreements may be more susceptible to parliamentary influence and differences between coalition partners may play out in parliamentary voting (Beasley and Kaarbo 2014; Oktay 2018). While the UK is infamously averse to coalition government, two of the last four general elections have resulted in ‘hung parliaments’.

4.5.3  Public Opinion: MPs may be conscious of public support or opposition to a treaty and to public opinion on the role of parliament in general or in a particular vote; MPs may also be affected by international public opinion and external expectations of their government; public opinion on a foreign policy rarely, however, determines the outcome of voting (Dieterich et al. 2008; Kaarbo and Kenealy 2016).

4.5.4    Leadership Style: Leaders differ in terms of how open they are to parliamentary involvement and how active and effective they are in their management of parliamentary input (Kaarbo 2018).

4.5.5     Government-Opposition Dynamics: Opposition parties are less likely to support initiatives by Governments. When in power, political parties tend to be more internationalist; parties in opposition have a general incentive to present themselves as an alternative to governments and their policies (Lewis, 2017; Wagner et al., 2018).


The Need for a Holistic Approach


6.1        Parliament’s role in treaty negotiations needs to be conceptualised holistically and with regards to the complex and sometimes counter-intuitive dynamics of international negotiations. Legislatures are a crucial actor in multilevel bargaining games. While ratification votes can lead to the rejection of negotiated agreements, the legislature’s ability to reject the agreement can also increase the government’s bargaining power. In this way, the legislature’s role is not best understood as a mere constraint, but rather as a dynamic partner in the process (Putnam 1988).

6.2        Ratification votes cast a long shadow on the entire process of negotiating and agreeing international treaties (Hagemann et al. 2019). Although parliamentary veto powers over foreign affairs are hardly ever used, they strengthen parliament’s influence substantially. Executives engage with the legislature more substantially and design their own negotiation strategy with parliament’s position in mind if parliament has a veto over the final outcome (Wagner, 2018).


6.3        Legislative scrutiny of international agreements is subject to a number of complex trade-offs between competing values, such as effectiveness, legitimacy, accountability, and secrecy. These trade-offs will need to be weighed against one another carefully, since they are all valuable in their own way in a democratic society. It is not the case that increasing parliamentarisation of treaty scrutiny necessarily improves one at the expense of any other. For instance, legitimacy may be undermined by conditions of intense partisanship and parliamentary involvement may increase the influence of the executive and contribute to a more ‘efficient’ outcome.


6.4        Any increase in Parliament’s competences will interact with existing norms and practices entrenched in the Westminster system. The effects of existing norms will need to be taken into account in any proposed changed. It may not be possible (or desirable) to replicate alternative models in the UK given pre-existing norms and modes of behaviour. For example, meaningful executive-legislative exchange under conditions of secrecy is facilitated in other countries through a combination of informal contacts and security clearances for legislators. The ‘conflictual’ nature of Westminster may make it difficult to maintain congenial executive- legislative relations and the level of discretion required.


29 May 2020




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